1. Field of the Invention
The present invention relates to a method and apparatus for processing an image, which receive an image and audio signal and compress the image and audio signal.
2. Description of the Related Art
As network technology has developed, network devices that provide various functions have appeared. A conventional codec used in Internet protocol (IP) network devices is realized using hardware or software, and has a structure for transmitting 1 channel output with respect to 1 channel input. Also, the conventional codec provides only 1 output in each channel even when there are multichannel inputs. In other words, only 1:1 input/output is possible in conventional IP network devices.
An IP network based image monitoring system independently requires at least 3 streams having a resolution of D1, a common intermediate format (CIF), and a quarter CIF (QCIF) according to each user, with respect to an input image signal. However, since only 1:1 input/output is possible in the conventional IP network devices, a system and method of providing 3 such streams in real time at low cost do not exist.
In other words, when a system includes one codec and the output resolution of the codec is converted according to a request of a user, all users who receive data from the codec must receive data with the converted output resolution. Accordingly, such a codec is unable to provide data having plurality of resolutions corresponding to different user requests. Also, when the resolution of the codec is converted to a high resolution, a user of a network bandwidth that can sufficiently receive a codec output stream in high resolution does not have any problem receiving the stream, but clients using a low speed network may be unable to smoothly receive the codec output stream.
When the number of codecs is increased to 3 so as to provide the 3 streams in real time, expenses for making the device increase, and the number of output resolutions is still limited by the number of codecs. Also, an image captured in an IP network device may be input in an interlace method. When a signal received in the interlace method is compressed and transmitted to a client or to another network device requesting the signal, the client or the other network device must perform a deinterlace operation in order to reproduce the signal.